Riparian Bird Occupancy in a Mountain Watershed in the Colorado Mineral Belt Appears Resilient to Climate-Change-Driven Increases in Metals and Rare Earth Elements in Water and Aquatic Macroinvertebrates

Acid rock drainage (ARD) impacts species composition in mountain streams. The potential impact for riparian birds experiencing elevated metal uptake by consumption of benthic invertebrates is concerning but not well studied. We investigated the influence and rare earth element (REE) content on presence breeding an ARD-impacted watershed Colorado, USA, where tree swallows nest boxes had previously been found to have concentrations at some sites. particular REEs were higher than those cadmium or lead. Avian point counts indicated that most bird detected present sites, rarely found. Occupancy models showed availability shrub forest habitat was a good predictor few habitat-specialists, REE water predictors avian presence. For other species, neither type nor quality important predictors. Overall, this study indicates climate-change-driven increases metals may